Fire hydrant valve seat flange

ABSTRACT

A fire hydrant having a valve seat flange with an integral liner. In one embodiment, the fire hydrant includes a valve seat flange disposed between a standpipe and a hydrant shoe. The valve seat flange includes a standpipe neck defining internal threads to directly connect to the standpipe and a base flange to directly connect to the hydrant shoe. The liner includes an outer peripheral edge that is entrapped within the valve seat flange and an inner circumferential surface defining threads for receiving the valve seat of a valve assembly. The present invention also discloses a process of manufacturing a valve seat flange, including the steps of: (a) manufacturing the liner, (b) incorporating the liner into a core with the outer peripheral region of the liner exposed, (c) placing the integral core/liner into the valve seat flange mold and (d) forming the valve seat flange around the liner with the valve seat flange entrapping the outer peripheral region of the liner.

BACKGROUND OF THE INVENTION

The present invention relates to fire hydrants and more particularly toa fire hydrant with a unique valve seat flange and a method formanufacturing the same.

Fire hydrants are commonplace in our society providing a ready source ofwater to, among other things, help confront fire hazards. Fire hydrantstypically remain idle for long periods of time. As a result, theinternal workings of the hydrant must be able to withstand long periodsof time in the presence of water without corroding or otherwise becomingnonfunctional.

With conventional fire hydrants, the flow of water through the hydrantis controlled by a valve. The valve is typically located below groundlevel within the hydrant shoe. A conventional valve includes a valveseat that is threaded in place within or adjacent to the hydrant shoe.The threaded seat permits the valve to be removed when maintenance isrequired. For example, the valve can be removed to permit replacement ofthe valve seal or to permit installation of a new valve. To ease removalof the valve, the valve seat is typically threadedly seated within abrass (or bronze) liner. The brass liner provides brass threads thatresist corrosion and facilitate removal of the valve even after extendedperiods of time. Often, the valve seat is also brass so that thethreaded interface between the valve seat and the brass liner includesintermeshing brass threads.

In many conventional constructions, the brass liner is sandwiched in oneway or another between a flange at the lower end of the standpipe andthe hydrant shoe. The typically sandwiched construction provides anumber of part interfaces that provide numerous potential leakage paths.Further, the sandwiched construction may not provide the strengthdesired in some applications. Additionally, the separate brass linerincreases parts inventory and complicates the assembly process.

SUMMARY OF THE INVENTION

The aforementioned problems are overcome by the present inventionwherein a fire hydrant is provided with a valve seat flange having anintegral liner. In one embodiment, the valve seat flange is disposedbetween the standpipe and the hydrant shoe, and includes a threadedbrass liner that is insert cast as an integral part of the valve seatflange.

In one embodiment, the valve seat flange includes an internally threadedstandpipe neck for threadedly mounting the valve seat flange to thelower end of the standpipe and planar base for connecting to the hydrantshoe. The liner may include a contoured outer peripheral region thatinterlocks with the valve seat flange to reduce the likelihood ofrotation of the liner with respect to the valve seat flange.

The valve seat flanges may be manufactured in a process including thesteps of: (a) manufacturing the liner, (b) incorporating the liner intoa core with the outer peripheral region of the liner exposed, (c)placing the integral core/liner into the valve seat flange mold, (d)forming the valve seat flange around the liner with the valve seatflange entrapping the outer peripheral region of the liner.

The present invention provides a hydrant with a simple and effectivevalve seat that provides the assembly with increased strength and alsoreduces the number of potential leak paths. Additionally, the integralliner eliminates the need for handling and assembly of a separate liner.The integral liner is also entrapped within the valve seat flange,thereby reducing the potential for axial movement of the liner withrespect to the flange.

These and other objects, advantages, and features of the invention willbe readily understood and appreciated by reference to the detaileddescription of the preferred embodiment and the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view of a fire hydrant incorporating a valveseat flange in accordance with an embodiment of the present invention.

FIG. 2 is a cross sectional view of the lower standpipe with the valveseat flange.

FIG. 3 is a top plan view of the valve seat flange.

FIG. 4 is a cross sectional view of the valve seat flange taken alongline IV-IV of FIG. 3.

FIG. 5 is a top plan view of the valve seat liner.

FIG. 6 is a cross sectional view of the valve seat liner taken alongline VI-VI of FIG. 5.

FIG. 7 is a cross sectional view of the valve seat liner taken alongline VII-VII of FIG. 5.

FIG. 8 is a cross sectional view of casting apparatus for use inmanufacture of one embodiment of the present invention.

FIG. 9 is a top plan view of the rough valve seat flange after castingand before machining.

FIG. 10 is a cross sectional view of the rough valve seat flange takenalong line X-X of FIG. 9.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

A fire hydrant incorporating a preferred embodiment of the presentinvention is shown in FIG. 1 and generally designated 10. The firehydrant 10 includes a valve 12 mounted within a valve seat flange 14.The valve seat flange 14 is disposed between the standpipe 16 and thehydrant shoe 18, and includes an integral liner 20 for threadedlyreceiving the valve assembly 22. The integral liner 20 provides anintegrated corrosion resistant liner for use in seating the valveassembly 22. The valve assembly 22 is threaded into the liner 20.

Fire hydrants are well known and accordingly will only be describedherein to the extent helpful in disclosing the present invention. Forpurposes of disclosure, the present invention is described in connectionwith a conventional WaterMaster® fire hydrant available from East JordanIron Works of East Jordan, Mich. The present invention is, however,readily incorporated into a wide variety of other fire hydrants, and thepresent invention should be interpreted as being limited to anyparticular fire hydrant construction. In summary, the fire hydrant 10 ofthe illustrated embodiment includes a hydrant shoe 18 which functions asan inlet, a valve seat flange 14 to receive the valve assembly 22, alower standpipe 16, an upper standpipe 24 and a top bonnet 26 thatsupports, among other things, the nozzle 28 and valve operating nut 30.

As discussed above, the valve seat flange 14 is interposed between thelower standpipe 16 and the hydrant shoe 18 to operatively receive thevalve assembly 22. The valve seat flange 14 includes a somewhat tubularbody 32 having a standpipe neck 34 at its upper end and a base flange 36at its lower end. Referring now to FIG. 2, the standpipe neck 34 isinterconnected with the lower standpipe 16. In the illustratedembodiment, the lower standpipe 16 is threadedly connected with thevalve seat flange 14. More specifically, in this embodiment, the lowerstandpipe 16 includes external threads 36 that are interfitted withinternal threads 38 defined in the standpipe neck 34. The base flange 36generally includes a planar peripheral flange 50 surrounding an annularrim 52. The peripheral flange 50 is generally planar providing a flatsurface for mounting to the upper mounting surface of the hydrant shoe18. The peripheral flange 50 defines a plurality of bolt holes 51 forintersecuring the valve seat flange 14 and hydrant shoe 18. The rim 52is closely fitted within the hydrant shoe 18 to center the valve seatflange 14 and strengthen the connection between the valve seat flange 14and the hydrant shoe 18. A lower o-ring 54 is preferably fitted to thebase flange 36 within and an o-ring seat 56 to facilitate a leaktightseal between the valve seat flange 14 and the hydrant shoe 18. The valveseat flange 14 includes a first reduced diameter portion 40, whichentraps the integral liner 20. The upper end of the first reduceddiameter portion 40 defines a surface to function as a stop for thethreaded lower standpipe 16. As described in more detail below, thevalve seat flange 14 is preferably formed about the liner 20 so that thetwo elements are integral with one another. The liner 20 is generallyring-shaped defining internal threads 42. The liner 20 and its internalthreads 42 are dimensioned to threadedly receive the valve assembly 22.The liner 20 is preferably manufactured from bronze, but may bemanufactured from other materials having sufficient strength andcorrosion resistance. For example, the liner may be brass in someapplications. In this embodiment, the liner 20 is manufactured in roughform for casting and is machined after incorporation into the valve seatflange 14. The rough liner 20 is shown in FIGS. 5-7. The rough liner 20of this embodiment includes a plurality of internal lugs 62 a-d thatinterlock with the core 100 to reduce the possibility of the liner 20rotating within the core 100. The lugs 62 a-d protrude from the innercircumferential surface of the liner 20. As described in more detailbelow, the inner circumferential surface is ultimately machined toprovide threads for interfacing with the valve assembly 22. Thismachining process removes the lugs 62 a-d. The rough liner 20 may alsodefine a plurality of grooves 64 a-f on the outer circumferentialsurface of the liner 20. The grooves 64 a-f interlock with the valveseat flange 14 when valve seat flange 14 is formed about the liner 20.This reduces the possibility of the liner 20 rotating within the valveseat flange 14. The grooves 64 a-f may be replaced by notches,protrusions or other variations in shape that provide an interlockbetween the liner 20 and the valve seat flange 14. The valve seat flange14 includes a second reduced diameter portion 44. The second reduceddiameter portion 44 is dimensioned to closely receive the valve seat 46of the valve assembly 22. The interior surface of the second reduceddiameter portion 44 is preferably machined to provide a smooth, cleansurface to interface with the o-rings 48 a-b of the valve seat 46. Thevalve seat flange 14 also defines an annular drain recess 57 and a pairof drain holes 58 a-b that permit water to drain from the standpipes 16,24 and bonnet 26 when the valve assembly 22 is in the closed position.The drain mechanism is generally conventional and therefore will not bedescribed in detail. Suffice is to said, however, that the drain recess57 and drain holes 58 a-b in the illustrated embodiment are defined inthe second reduced diameter portion 44 so that they are disposed betweenthe valve seat o-rings 60 a-b.

A preferred method for manufacturing the valve seat flange 14 using acasting process will now be described with reference to FIGS. 8-10. Therough liner 20 is manufactured separately from the remainder of thevalve seat flange 14 (See FIGS. 5-7). The liner 20 is preferably castfrom bronze or brass using conventional casting tools and methods, butmay be machined or otherwise formed. The liner 20 is not necessarilymanufactured from bronze or brass and may be manufactured from othermaterials having sufficient strength and corrosion resistance.

The liner 20 is insert cast into valve seat flange 14 using aconventional casting core, for example, sand core 100. The core 100maintains the liner 20 in the correct position during the process ofcasting the valve seat flange 14. The rough liner 20 is integrated intothe core 100 using conventional core manufacturing techniques andapparatus. As shown in FIG. 8, the rough liner 20 is integrated intocore 100 with its outer peripheral region exposed, and morespecifically, that portion of the outer periphery of the liner 20 thatis to be entrapped within the valve seat flange 14.

The valve seat flange 14 is cast, for example, from a ductile iron. Inthis embodiment, the valve seat flange 14 is cast using a conventionalsand casting apparatus 90. In summary, a pattern (not shown) of thevalve seat flange 14 is preformed. The pattern is shaped to occupy thespace of the valve seat flange 14 and the core 100. The pattern ispressed into the cope 102 and drag 104 to define opposed portions of thecasting cavity 106. A runner gate system (not shown) is also defined inthe cope 102 to permit the desired molten material to be poured into thecavity 106. Before closing the cope 102, the core 100 is placed in thecavity 106 where it remains during the casting process. The cope 102 isthen closed on top of the drag 104 with the cope 102 and drag 104cooperatively defining a cavity 106 surrounding at least portions of thecore 100 in the shape of the valve seat flange 14. Molten material, suchas ductile iron, is then poured into the cavity 106 through runner gatesystem. The molten material flows down into the cavity 106 where it ispermitted to cure. After curing, the completed part is removed from thecope 102 and drag 104. The core 100 is broken apart and removed fromwithin the part leaving behind the rough liner 20 entrapped within thevalve seat flange 14. The rough valve seat flange 14 is shown in FIGS. 9and 10. As shown, the liner 20 continues to include lugs 62-a-d. Inaddition, the interfacing surfaces of the valve seat flange 14 remainrough. The valve seat flange 14 is then finished as desired, forexample, by machining to remove the runner gate system and any undesiredrough surfaces. In this embodiment, the finishing process includes thestep of forming internal threads 38 in the standpipe neck 34 tothreadedly receive the lower end of the lower standpipe 16. Also, thebottom surface of the base flange 36 is machined to provide a smoothinterface with the top flange of the hydrant shoe 18. Similarly, theinterior surface of the second reduced diameter portion 44 is machinedto provide a smooth interface with the valve seat 46 and valve seato-rings. The annular drain recess 57 and drain holes 58 a-b are alsopreferably, but not necessarily, machined into the valve seat flange 14after the casting process is complete. Further, in this embodiment, theinner circumferential surface of the liner 20 is machined to formthreads 42. The threads 42 may, however, be formed before or after thevalve seat flange 14 casting process.

The valve seat flange 14 is installed in the hydrant 10 by aligningflange 14 and shoe 18 so that the rim 52 is fitted within the shoe 18.The valve seat flange 14 is then secured to hydrant shoe 18, forexample, by bolts or other fasteners (not shown) extending through thebolt holes 51 in the base flange 36 and the corresponding top flange ofthe hydrant shoe 18. The valve assembly 22 may then be installed withinthe valve seat flange 14. The valve seat 46 is threaded into the liner20 creating a brass-on-brass threaded interface. The valve seat 46 isthreaded into the liner 20 until the bottom end of the valve seat 46abuts the upper surface of the second reduced diameter portion 44. Thishelps to ensure proper positioning of the valve assembly 22 within thevalve seat flange 14. The lower standpipe 16 is then installed on thevalve seat flange 14. The threaded lower end of the standpipe 16 isthreaded into the standpipe neck 34. The lower standpipe 16 is threadedinto the valve seat flange 14 until the bottom end of the lowerstandpipe abuts the top surface of the first reduced diameter portion40. In that way, the first reduced diameter portion 40 helps to ensureproper positioning of the lower standpipe 16. The remaining portions ofthe hydrant 10 are assembled in a conventional manner.

The above description is that of a preferred embodiment of theinvention. Various alterations and changes can be made without departingfrom the spirit and broader aspects of the invention as defined in theappended claims, which are to be interpreted in accordance with theprinciples of patent law including the doctrine of equivalents. Anyreference to claim elements in the singular, for example, using thearticles “a,” “an,” “the” or “said,” is not to be construed as limitingthe element to the singular.

1-6. (canceled)
 7. A method for manufacturing a valve seat flange for afire hydrant, comprising the steps of: manufacturing a liner; forming acasting core incorporating the liner, an outer peripheral portion of theliner being exposed; inserting the core incorporating the liner into acasting cavity; casting a valve seat flange by pouring molten materialinto the casting cavity about the core, the outer peripheral portion ofthe liner being entrapped within the material forming the valve seatflange; and removing the core from the cast valve seat flange leavingthe liner integral within the valve seat flange.
 8. The method of claim7 further comprising a step of forming internal threads on an internalcircumferential surface of the liner.
 9. The method of claim 8 furtherwherein said step of manufacturing said liner includes a step of formingat least one of a protrusion and a recess in the outer peripheralsurface of said liner.
 10. The method of claim 8 wherein said castingstep includes the step of forming a standpipe neck to directly mount toa hydrant standpipe.
 11. The method of claim 10 wherein said castingstep includes the step of forming a base flange to directly mount to ahydrant shoe.
 12. The method of claim 11 wherein said casting stepincludes the step of forming an inner rim within the base flange, theinner configured to be fitted within a hydrant shoe.
 13. The method ofclaim 12 further including the step of forming an o-ring seat in atleast one of the base flange and the inner rim.
 14. The method of claim13 wherein the liner is manufactured from one of bronze and brass, andthe valve seat flange is manufactured from ductile iron. 15-19.(canceled)